Classification
333 - Economics of land & energy
600 - Technology
320 - Political science
4
100 - Philosophy & psychology
3
363 - Other social problems & services
3
551 - Geology, hydrology & meteorology
3
300 - Social sciences
2
330 - Economics
2
620 - Engineering & allied operations
2
140 - Specific philosophical schools
1
170 - Ethics
1
200 - Religion
1
301 - Sociology & anthropology
1
370 - Education
1
581 - Specific topics in natural history
1
610 - Medicine & health
1
700 - The arts; fine & decorative arts
1
900 - History & geography
1